The invention relates to a method for fitting a breaking device tool with a bearing, a breaking device and a tool bushing used for a bearing. The breaking device comprises at least a frame, a tool and a percussion device. By means of a percussion element in the percussion device, compression stress pulses are generated in the tool, which transmits them further to material to be broken. In a bearing space around the tool a bearing bushing is arranged, a sliding surface on the inner periphery of the bearing bushing fitting the tool with a bearing to be movable in the axial direction of the tool. The object of the invention is described in more detail in the preambles of the independent claims.
A breaking hammer is a breaking device used as a supplementary device of an excavator or another basic machine when the intention is to break for instance rock, concrete or other relatively hard material. The percussion device of the breaking hammer is used to give compression stress pulses to a tool attached to the breaking hammer, the tool transmitting the stress pulses to the material to be broken. At the same time, the tool is pressed against the material to be broken, whereby the effect of the stress waves and pressing causes the tool to penetrate into the material to be broken, which results in breaking of the material. The tool of the breaking device is mounted on a bearing in the frame of the breaking device in such a way that it can move in the axial direction during the breaking. The tool is usually mounted on a slide bearing by means of one or more bearing bushings. In known solutions, the bearing bushing is attached to a tool bushing that is, in turn, attached to the frame of the breaking device. The bearing bushing is a slide bearing that wears in use, due to which it has to be changed from time to time. A problem with known solutions is that it is difficult and slow to change a worn bearing bushing in working site conditions.